I figure Goldrush should be just fine in the Omaha area. They ripen over here in more clouds, cooler eastern Iowa (zone 5a/b). They are reliable enough here that the local U-Pick and cidery gets a good portion of their hard cider production from Goldrush (Wilsons out of Iowa City - not sure how far west in IA they distribute).
I like Crimson Crisp enough that I planted it in my own Version 2.0 orchard this spring after moving last year. I think it is a solid apple if you are into scab resistant varieties. It has a good apple flavor and can get a subtle lemon/citrus flavor some years.
Liberty is a good enough apple that seems to be very reliable, so it made the move with me as a new tree. It is precious to the max on G.935. It was my favorite tree for rootstock and apple combo. Just foolproof for production. Scab and fireblight resistant. Keeps until Christmas for me, but folks like @marknmt I believe have stored them longer
Suncrisp, of course. I’m among its highest boosters here.
Empire does well here (Mac x Delicious but mostly Mac). Chieftain (Jonathon x Delicious) came from ISU, it is solid in our climate. These two fit in the classic Mac/North American vinous category.
Kidd’s Orange Red was high on my list when I planted my 1st orchard but I didn’t like the texture and the flavor wasn’t quite there for me. I did not replant it. I might add it back later as a graft.
Sweet Sixteen is ripe Labor Day here (9/26 seems too late). If grown on drier soil it gives the full range of Cherry and Anise/Licorice flavor depending on harvest date and storage length. If grown on loam or irrigated it seems bit less flavorful and is just a good apple with slight hints of the cherry.
I’d personally say why not grow some earlier apples… why wait til September? Japanese Beetles aren’t that bad, at least not every year. My favorites are Zestar! and Williams Pride. Both also keep well compared to other August apples.
Also search for @Chikn’s posts. I believe he has made comments about what works for him in central Iowa. I think he really likes Baldwin. Edit: here are his 2017 and 2018 posts.